+" strip trailing whitespace
+function! StripWhitespace(line1, line2, ...)  " {{{2
+  let s_report = &report
+  let &report=0
+  let pattern = a:0 ? a:1 : '[\\]\@<!\s\+$'
+  let oldview = winsaveview()
+  exe 'keepjumps keeppatterns '.a:line1.','.a:line2.'substitute/'.pattern.'//e'
+  if oldview != winsaveview()
+    redraw
+  endif
+  call winrestview(oldview)
+  let &report = s_report
+endfunction  " }}}2
+command! -range=% -nargs=0 -bar Untrail keepjumps call StripWhitespace(<line1>,<line2>)
+nnoremap <silent> <leader>ww :Untrail<CR>